How to enable a disables GameObject

Hi! I wanna activate an disabled GameObject at the end of and animation state, but I alway get the error "NullReferenceException: Object reference not set to an instance of an object". What I do wrong?

Code (CSharp):

1.  public override void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
2.     {
3.         GameObject.Find("GridButton").gameObject.SetActive(true); ;
4.  
5.  
6.     }

Thank You!

 

GameObject.Find only searches for active game objects. You will need a different method of identifying the object you want to activate.

The most common way to do this is to create a public variable and then assign it to the appropriate object via the inspector, but there's several ways of acquiring object references, and which one is best depends on the circumstances.

 

Which ways are possible? Im totally new to the engine. The way with the public variable doesnt work, Im just able to add prefabs to an public gameobject variable but no excisting gameobjects of the scene. Thx!

 

Is the animator that OnStateEnter gets as a parameter, attached to the game object that you're trying to enable? Because in that case, I think you should be able to do:

Code (Csharp):

1.  
2. public override void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
3. {
4.     animator.gameObject.SetActive(true);
5. }
6.  

 

I somehow doubt this is the case because if the gameObject the Animator is attached to is disabled, the animator wouldn't be running.

hey OP, Are you aware that the active state of the GameObject might actually be something you can animate without any extra code? Depending on where the object lives in your hiearchy, you can just add it as a property in your Animator!

Here's a screenshot from one of my projects showing IsActive as an animatable property:

 

Thanks for the tips But unfortunately I havent found a solution with it. I cant see "Base" in my Animation Window. Why is that? Thanks

 

In my case I literally have an object called "Base" in my prefab's hierarchy that this screenshot came from.



In general I don't think you can set active on the ROOT object of the animator's hierarchy, if that's the case in your case. if possible see if you can move the component or object you're looking to reactivate to a child object of the one that has the animator on it.

 

Prefabs can generally only have references to other parts of the prefab, but objects in a scene should be able to refer to other objects in the same scene. Is the object that needs the reference a prefab? Instead of using the prefab directly, could you create an instance of that prefab in the appropriate scene, and use that? (Possibly keeping it inactive until you need it.)

Alternately, can you store a reference to the object you need in a variable on some other object on the scene that would be easier to find? Once you find one component, you can follow its public variables to other components that it "knows about".



FindObjectOfType (and its plural version) have an optional parameter that allows them to search for inactive objects.

I believe you can get to inactive objects through parent/child relations using Transform.Find and other hierarchical functions on the Transform class, but note that these only allow you to get a direct parent/child, so if you want to traverse multiple levels of hierarchy it requires multiple steps, and you need to know the right place to look at each step.

You can store references to certain objects in public static variables somewhere, which will be accessible to whatever script needs them. (Static variables can be accessed without needing a reference to any particular class instance.) This is especially used for classes following the singleton design pattern. But you need to be careful you don't end up with multiple instances of a class all trying to use the same static variable as if it were just for them, or they'll overwrite each other.

 

I now stored the objects I wanna activate in a new script of a new gameobject called "Referencer". I assigned all objects to the References via Inspector. Now the problem is, Im not able to access the scirpt (and the variables) of the Referencer from my Animation Script. Maybe it is a problem Im in a "StateMachineBehaviour"?

 

Post the code for the variables you are trying to reference and how you are trying to reference them.

 

It WORKS! Thanks for your help I had just a stupid naming error. I get it done with an extra referencer object that has the diasbled objects as variables